The primary objective of the Imaging and Radiation Oncology (IROC) Group is to provide scientific and technical expertise for incorporation of appropriate, integrated quality Assurance (QA) and image data management for both imaging and radiotherapy (RT) in applicable trials conducted by the National Clinical Trials Network (NCTN) Program and other NCI funded clinical trial groups (NCORP and ETCTN). The physical IROC QA Centers are distributed in 4 main locations and are administratively organized through the American College of Radiology (ACR). The QA Centers include IROC Houston, IROC Ohio, IROC Rhode Island, and IROC Philadelphia. The Advanced Technology QA Center (ATC) located at Washington University, St. Louis will provide their expertise and consultation services to IROC as needed. IROC capitalizes on existing infrastructure and expertise at QA centers currently providing services to the NCI?s clinical trial programs. Work flows, processes and information systems have been enhanced taking into account the best practices and standards in an integrated vision across NCI?s clinical trials. The interdependencies between imaging and RT are synergized eliminating duplication of services and optimizing efficient and effective workflows. A major strength of IROC is the development of consistent standard operating procedures for all imaging and RT aspects of the NCTN, NCORP and ETCTN (NCI Groups) and to facilitate a seamless flow of imaging and RT patient case datasets across the networks. IROC?s organizational structure allows the delivery of a broad array of imaging and RT QA services including Site Qualification; Trial Design Support; Credentialing; Data Management (Pre- and Post-treatment Case Review); and Case Review. An information technology infrastructure is used that harmonizes IROC services, data collection, assessment and management for the NCI Groups? clinical trials. IROC implements programs that assure consistent high quality imaging and RT planning/delivery across the NCTN participating sites. IROC members collaborate with the NCI, NCI Groups, and disease/modality committees within each Network Group to provide an optimum and effective imaging and RT core service. The IROC Group will analyze QA data obtained prospectively/retrospectively and the correlation it might have with clinical trial outcomes to better determine and prioritize appropriate QA activities that maximize their benefit to clinical trials.